A. Field of the Invention
This invention relates to telephone equipment and related application programs;
B. Related Art
A programmable office telephone typically includes a number of keys for performing user definable functions. For example, by way of the telephone keyboard or an applications program running on a connected computer, keys can be selectively programmed to activate such functions as mute, hold, do not disturb or conference call. In many such telephones, each key has an adjacently located light which is automatically turned on when the function for which the key has been defined is activated. For example, a key depression may place the phone in Do Not Disturb mode and the associated, adjacent light will turn on to indicate that fact to the user. Thus, in such telephones, the keys and lights are said to be both physically and logically paired. That is to say, a particular light is only turned on in response to the activation of a feature caused by the depression of the adjacent key.
In some prior art telephones there are lights which are neither adjacent to any key nor associated with any defined key function. For example, in some prior art ROLM telephones, there is a standalone "call waiting" light which is activated directly by way of a command from the PBX rather than in direct response to depression of a corresponding key on the face of the telephone. Similarly, in some prior art telephones there are standalone keys which have no adjacent or associated light. For example, in many telephones there are standalone keys (i.e. keys not having an associated light) dedicated to automatic dialing of prestored telephone numbers.
It is known in the art to provide a telephone with means to maintain the correspondence between a given feature and a physical key/light pair. For example, it is known to provide the firmware within the key and light control logic with access to tables which have definitions for each key. When a key is depressed, a feature activation code (key definition) is sent uplink to notify the switch (e.g. the PBX) of the user's action. In response to receipt of the feature activation code, the PBX returns an LED cadence command (feature indication). When the telephone receives the cadence command for a feature, it scans the tables and turns on all lights for which the feature indication matches the key definition.
While the use of physical/logical pairing for some functions and standalone keys and/or lights for other functions can be useful, such configurations can crowd the face of the telephone and add to the expense of manufacture. Thus, there is a need for a more flexible manner of providing activation and indication of standalone functions.